New approaches for service composition based on graph models

In this paper we present web service composition problem as search problem in AND/OR Service Dependency Graph (SDG). In general web services take multiple inputs and produce single output. For this reason we concentrated on Multi-input, Single output web services composition. We proposed two algorithms for finding the composition given a service request. First algorithm finds the composition by generating all the paths from input nodes to output node and merging the paths. In Second algorithm we have incorporated cost parameters for web services and algorithm finds the minimal composition for the given request. We have evaluated our algorithms experimentally and results are shown.